DESCRIPTION: The project evaluates effectiveness of five, theoretically motivated treatment programs for young children with developmental, language-based reading disabilities. Treatments are based upon evidence that: 1) developmental reading problems are due to multiple, core linguistic and cognitive deficits, primarily in phonological awareness; naming/processing speed, and metacognitive control; and 2) data demonstrating the effectiveness of treatments that address more than one of the deficits are most effective. This project integrates three proven treatment modules (PHAB/DI-Phonological Analysis and Blending; WIST-Word Identification Strategy Training, RAVE-O-Retrieval-Rate, Accuracy, Vocabulary Elaboration, and Orthography) into a comprehensive triple-focus intervention, comparing it to two dual-focus programs (PHAB/DI + WIST, PHAB/DI + RAVEO) and a curriculum control condition. Two additional enhanced treatment programs, one that includes spelling/writing training, the other comprehensive fluency training, will each be integrated with the triple-focused program. All treatment programs employ similar format, taught by trained research teachers hired for the project, and independently monitored for treatment integrity. In addition to treatment comparisons this project also evaluates the impact of developmental timing of the intervention (starting in 1st, 2nd, or 3rd grade), differing levels of intervention intensity (hours of instruction-0, 35, 0, 105, 140, 175, 210, 245, 2800, teacher/student ratios-1:1, 1:4, 1:classroom), and the role of individual differences, particularly those related to different RD definitions, or cognitive subtypes, on reading outcomes. In all, over 432 children, selected to represent the full range of race, SES, and IQ levels, will receive interventions and be longitudinally followed until 4th grade. Three treatment sites (Atlanta, Boston, Toronto) are used to enhance generalizability and to address dialect, cultural, socioeconomic, and curriculum differences within schools. Repeated measure designs, multiple and logistic regression, and growth curve modeling will be used to evaluate treatment outcomes in relation to individual differences on standardized and experimental measures, particularly those related to word identification, fluency, and reading comprehension.